1. Field of the Invention
The present invention is generally related to the computer graphics rendering of dynamic scenes subject to global illumination and, in particular, to the real-time rendering of complex, deformable geometries with global illumination computed shading to obtain realistic scene lighting.
2. Description of the Related Art
A key requirement in the realistic rendering of computer generated graphical images is the accurate computation of the interdependent light distribution among the various element surfaces within the image scene. To address the accurate synthesis of scene lighting, various physics-based global illumination techniques have been developed. These techniques, including radiosity, ray tracing, and photon mapping, approach realistic image rendering by directly simulating the physical phenomenon of light distribution within a set three-dimensional environment. Many of the theoretical and practical implementation issues of physics-based global illumination techniques are explored in Advanced Global Illumination by Philip Dutre, Philippe Bekaert, and Kavita Bala, AK Peters, Ltd., (July 2003).
The principal limitation of known physics-based global illumination techniques is the computational intensity of the physics-based simulations. The computational requirements of the algorithms implementing the simulations for scenes of even modest complexity well-exceed usable display frame-rates. Trade-offs, such as reducing the simulation accuracy, directly impact the realism of the rendered scene. Other trade-offs, such as pre-computation of light distribution for static elements, have been explored. Unfortunately, all but a small portion of a typical scene has to be statically pre-computed in order to achieve useable frame-rates. This results in quite visible lighting inaccuracies whenever the any dynamic element is repositioned within the overall scene. Even with the substantial improvements in the processing performance of general purpose central processing units (CPUs) and peripheral graphical processing units (GPUs), known physics-based global illumination techniques are conventionally accepted as too computationally expensive achieve real-time rendering of fully dynamic scenes.
Consequently, a need exists for a physics-based global illumination technique that is fully capable of the real-time rendering of fully dynamic scenes.